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Learning: Responding to Our Environment } Learning is all about understanding various responses to stimuli & their affects on long term patterns of behavior. } Core questions: § Where does learned behavior come from? § How do we “know” what to do in response to the environment? • Answers lie in some form of “change in behavior.” • After “learning,” we can do something new that we couldn’t do before. © 2016 Cengage Learning. Reflexes vs. Instincts vs. Learning } Reflexes are fast, responses to stimuli § Mediated by circuits in the spinal cord and brainstem § Serve to promote your welfare. } Simple, inflexible, not learned through experience (i.e., are innate) § Disadvantages of being inflexible and not very adaptable to change. • E.g., goose bumps Responding to Our Environment © 2016 Cengage Learning. Reflexes vs. Instincts vs. Learning } Instincts are innate patterns of behavior § Elicited by environmental stimuli that do not require learning. § Do not need to be learned/are inflexible. } More complex than reflexes, and are mediated by processing higher in the brain. • E.g., Contagious yawning § Yawning in general => cooling the brain § Might be related to empathy -- synchronize the arousal state of whole groups. Responding to Our Environment © 2016 Cengage Learning. Reflexes vs. Instincts vs. Learning } Learning is a relatively permanent change in behavior (or the capacity for behavior) due to experience. § The core of this definition is “change in behavior.” § After learning, we can do something new that we couldn’t do before. • Enormous adaptive advantage! Responding to Our Environment © 2016 Cengage Learning. Learning vs. States } Not all changes in behavior are due to learning. § E.g., maturation; brain damage } Definition limits changes to those that result from experience. § “Relatively permanent change” § Brief or unstable changes/states are not a result of learning. • e.g., mood; sickness Responding to Our Environment © 2016 Cengage Learning. Nonassociative Learning • Nonassociative learning • Changes in the magnitude of responses to a single stimulus – not the formation of connections between stimuli. • Two important types: • Habituation reduced reactions to repeated experiences. • E.g., 1st night in a hotel vs. 2nd night • Sensitization increases reactions to stimuli following exposure to one strong stimulus. • E.g., earthquakes Responding to Our Environment © 2016 Cengage Learning. Associative Learning } Occurs when we form connections among stimuli and/or behaviors § Classical conditioning § Operant conditioning Responding to Our Environment © 2016 Cengage Learning. Classical Conditioning } This section covers: § Principles, phenomena, and applications of classical conditioning © 2016 Cengage Learning. DROOL WARNING! © 2016 Cengage Learning. Classical Conditioning } Pavlov distinguished stimuli and responses into two forms + “neutral” § “Conditioned” = things that must be learned § “Unconditioned” = things that are reflexive/occur without any learning. • Conditioned stimulus (CS) refers to an environmental event whose significance is learned. • Unconditioned stimulus (UCS) has innate, built-in meaning to the organism. • Conditioned responses (CRs) are learned reactions • Unconditioned responses (UCRs) don’t need to be learned; they appear without prior experience with a stimulus. © 2016 Cengage Learning. Classical Conditioning } Let’s imagine a scenario in which we are conditioning a dog to salivate to the sound of a metronome: § Dogs salivate (UCR) when the see food (UCS) § During conditioning, the sound of the metronome (NS) is followed by food (UCS), which produces salivation (UCR). } The repeated pairing of the sound and food forms the association between NS & UCR (i.e., learning occurs). § After conditioning, the sound of the metronome (now a CS) by itself is sufficient to produce salivation (now a CR). • Learning has occurred! © 2016 Cengage Learning. The Classical Conditioning Process – Before Conditioning Classical Conditioning © 2016 Cengage Learning. The Classical Conditioning Process – During and After Conditioning Classical Conditioning © 2016 Cengage Learning. Classical Conditioning Terms Term Abbreviation Definition Unconditionedstimulus US Astimulusthatnaturallyandreliablyevokesa response Unconditioned response UR Theresponsethatisnaturallyandreliably elicited bytheunconditionedstimulus Neutralstimulus NS Astimulusthatdoesnotinitiallyelicit the unconditionedresponse Conditionedstimulus CS Astimulusthatwasonceneutral but,through associationwiththeUS,nowelicits aresponse Conditionedresponse CR Afterconditioninghasoccurred, theresponse thatiselicited bytheconditionedstimulus Classical Conditioning © 2016 Cengage Learning. Contingency and Contiguity } Acquisition refers to the development of a conditioned response. } Acquisition requires contiguity: § Close proximity in time between the conditioned stimulus (CS) and the unconditioned stimulus (UCS). • Learning is typically most effective when the CS appears right before the UCS. Classical Conditioning © 2016 Cengage Learning. Contingency and Contiguity } Acquisition also requires contingency § An association between the conditioned stimulus (CS) and unconditioned stimulus (UCS). • Learning about a consistent signal is easier than learning about a signal that only occurs some of the time. § When contingency is high, the CS reliably predicts the appearance of the UCS Classical Conditioning © 2016 Cengage Learning. Contingency and Contiguity CS = Ringing Bell; UCS = Steak Classical Conditioning © 2016 Cengage Learning. Stimulus Generalization and Discrimination § Stimulus Generalization: Once a CR is acquired, there is a tendency to respond to stimuli that are similar to the CS. § Stimulus Discrimination eventually allows us to make fine distinctions between the implications of stimuli. Classical Conditioning © 2016 Cengage Learning. Extinction and Spontaneous Recovery § Conditioned responses will undergo extinction if the association between the CS and the UCS is broken. § E.g., Continue to expose dog to the ticking of the metronome without providing any food • Dog will eventually stop salivating in response to the sound. § Extinction is not the same thing as forgetting (i.e., new learning that overrides old learning). § Evidence for this from observed spontaneous recovery • The reappearance of CRs following periods of rest between sessions of extinction training. Classical Conditioning © 2016 Cengage Learning. Operant Conditioning } This section covers: § Principles, phenomena, and applications of operant conditioning © 2016 Cengage Learning. Thorndike’s Law of Effect } Behaviors followed by pleasant or helpful outcomes would be more likely to occur in the future } Behaviors followed by unpleasant or harmful outcomes would be less likely to occur. Operant Conditioning © 2016 Cengage Learning. Thorndike’s Law of Effect } Based on observations off of cats’ behavior in a puzzle box he had constructed. § To escape required a complete sequence of behaviors. § Through trial-and-error learning, cat would generally escape faster on successive trials. Operant Conditioning © 2016 Cengage Learning. Skinner and Behaviorism } B.F. Skinner introduced the term operant conditioning (OC) to the study of the law of effect. } In CC the organism does not actively choose to operate on the environment to produce some consequence § i.e., The response is forced from the animal. § Skinner referred to classically conditioned behavior as respondent behavior. Operant Conditioning © 2016 Cengage Learning. Skinner & Behaviorism } In OC the organism makes a choice to respond to its environment § KEY: In OC learning, behavior operates on the environment to produce some consequence. Operant Conditioning © 2016 Cengage Learning. Consequences of Conditioning } In OC learning occurs via various consequences of behaviors. § Consequences must be highly salient (very desirable or very unpleasant) to be effective. • Important: some types of consequences increase behaviors and some types decrease behaviors. Operant Conditioning © 2016 Cengage Learning. Consequences of Conditioning } Skinner divided consequences into four classes: positive reinforcement, negative reinforcement, positive punishment, and negative punishment. § Both types of reinforcement increase their associated behaviors § Both types of punishment decrease associated behaviors } KEY: We all have our own unique set of effective reinforcers and punishers! § i.e., The identity of a reinforcer or punisher is defined by its effects on behavior -- not by an intrinsic quality of the consequence itself! Operant Conditioning © 2016 Cengage Learning. Consequences of Conditioning } Add some element to one’s environment (“positive”), or remove an element (“negative”) } This can lead to an increase in the behavior (“reinforcement”), or a decrease in the behavior (“punishment”) Add stimulus to environment Remove stimulus from environment Make behavior more frequent Positive reinforcement Negative reinforcement Make behavior less frequent Positive punishment Negative punishment } People constantly get these confused!© 2016 Cengage Learning. Operant Conditioning Positive Reinforcement • Positive reinforcement increases the frequency of its associated behavior by providing a desired outcome. Operant Conditioning © 2016 Cengage Learning. Negative Reinforcement • Negative reinforcement involves the use of unpleasant consequences to increase the frequency of an associated behavior. • Behavior is strengthened through negative reinforcement when the behavior results in the removal or termination of something unpleasant. • Many everyday behaviors are maintained by negative reinforcement. • We buckle up in our cars to turn off annoying beeps, • Open umbrellas to avoid getting wet • Scratch an insect bite to relieve the itch. Operant Conditioning © 2016 Cengage Learning. Negative Reinforcement Operant Conditioning © 2016 Cengage Learning. Positive Punishment } Positive punishment refers to applying an aversive consequence that reduces the frequency of or eliminates a behavior. § This cat’s behavior (scratching the furniture) is punished by adding an unpleasant outcome (a squirt from a water bottle) Operant Conditioning © 2016 Cengage Learning. Negative Punishment } Negative Punishment: Removing a stimulus from the environment to make a behaviror less frequent. § E.g., Taking a privileges/objects away from people is a form of negative punishment. } Other notes about punishment: § Consequences have to matter to the person or animal receiving them (i.e., significance). § Immediate punishment is much more effective than delayed punishment (i.e., immediacy). § Effective punishment must follow uniform application (i.e., consistency). © 2016 Cengage Learning. Operant Conditioning A Bit of Review Type of Learning Cognitive Process Examples Associative Form new connections among stimuli and behaviors • Classical Conditioning • Operant Conditioning Nonassociative Change the magnitude of responses to a kind of stimulus • Habituation • Sensitization Observational Learning by watching the actions and experience of another • Imitation Operant Conditioning © 2016 Cengage Learning. A Bit of Review Classical Conditioning Operant Conditioning Association between conditioned & unconditioned stimuli Association between behavior & consequences Organism responds to environment Organism acts on environment Behavior is reactive Behavior is instrumental Best with involuntary behaviors Best with voluntary behaviors Operant Conditioning © 2016 Cengage Learning. A Bit of Review Add stimulus to environment Remove stimulus from environment Increase behavior Positive reinforcement Negative reinforcement Decrease behavior Positive punishment Negative punishment Operant Conditioning © 2016 Cengage Learning. Positive Reinforcement A dog that begs is given a treat; it will learn to beg more often. Operant Conditioning © 2016 Cengage Learning. Positive Punishment A kitten that scratches is scolded; it will learn not to scratch. Operant Conditioning © 2016 Cengage Learning. Negative Reinforcement A woman hits the snooze button on her alarm; she will start hitting the snooze button more often. Operant Conditioning © 2016 Cengage Learning. Negative Punishment A girl who breaks a rule has to give up her phone (removing privileges). Operant Conditioning © 2016 Cengage Learning. Schedules of Reinforcement } Continuous § Every time a behavior occurs } Partial § Ratio or interval § Fixed or variable Operant Conditioning © 2016 Cengage Learning. Schedules of Reinforcement • A fixed ratio (FR) schedule requires that a behavior occur a set number of times for each reinforcer. • Reinforcers in variable ratio (VR) schedules are given after a fluctuating number of behaviors. • In a fixed interval (FI) schedule, as set amount of time must pass before reinforcement becomes available following a response. • In a variable interval (VI) schedule the time interval is allowed to fluctuate around some average amount over the course of a session. Operant Conditioning © 2016 Cengage Learning. Effects of Reinforcement Schedules } Variable Schedules > Fixed Schedules. § FI low rates of responding at the beginning of the interval and accelerated responding at the end. } Which is better? § VR reinforcement leads to rapid and consistent increase in behavior. § FR and FI: Behavior tends to drop immediately after a reward, and speed close to next reward. § VI reinforcement behavior is slow to increase, but steady. Operant Conditioning © 2016 Cengage Learning. Effects of Reinforcement Schedules Operant Conditioning © 2016 Cengage Learning. Shaping } What happens if you want to increase the frequency of a behavior that rarely or never occurs? } Shaping via the method of successive approximations § Begin by reinforcing spontaneous behaviors that are somewhat similar to the target behavior we want to train. § Use gradually more stringent requirements for reinforcement until the exact behavior we want occurs. Operant Conditioning © 2016 Cengage Learning. Bandura’s Experiments • Some, but not all, learning occurs via reinforcement. • Bandura & Social Learning Theory. • • i.e., learning via modeling others’ behavior (aka. observational learning) • “Bobo Doll Experiments” Children watched films in which a woman beat up the Bobo doll. • E.g., hit with a mallet, sat on it, threw in the air. • Child were then placed them in a room alone with the Bobo doll and observed their behavior without their knowledge. If the children imitated the characteristic behaviors of the model, then learning had occurred. Operant Conditioning © 2016 Cengage Learning. Bandura’s Experiments Bobo Doll Video © 2016 Cengage Learning.